]> wimlib.net Git - wimlib/blobdiff - src/win32_capture.c
Use dynamically-sized path buffer when scanning files
[wimlib] / src / win32_capture.c
index a93427ec46a1d60a02642b5fc721b3946a1c64a8..75c5e66f56132d494b59356f1619e02a3644e5bf 100644 (file)
@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (C) 2013-2016 Eric Biggers
+ * Copyright (C) 2013-2017 Eric Biggers
  *
  * This file is free software; you can redistribute it and/or modify it under
  * the terms of the GNU Lesser General Public License as published by the Free
@@ -58,10 +58,10 @@ struct winnt_scan_ctx {
 };
 
 static inline const wchar_t *
-printable_path(const wchar_t *full_path)
+printable_path(const struct winnt_scan_ctx *ctx)
 {
        /* Skip over \\?\ or \??\  */
-       return full_path + 4;
+       return ctx->params->cur_path + 4;
 }
 
 /* Description of where data is located on a Windows filesystem  */
@@ -457,7 +457,7 @@ read_win32_encrypted_file_prefix(const wchar_t *path, bool is_dir, u64 size,
        if (err != ERROR_SUCCESS) {
                win32_error(err,
                            L"Failed to open encrypted file \"%ls\" for raw read",
-                           printable_path(path));
+                           path);
                return WIMLIB_ERR_OPEN;
        }
        err = ReadEncryptedFileRaw(win32_encrypted_export_cb,
@@ -467,14 +467,14 @@ read_win32_encrypted_file_prefix(const wchar_t *path, bool is_dir, u64 size,
                if (ret == 0) {
                        win32_error(err,
                                    L"Failed to read encrypted file \"%ls\"",
-                                   printable_path(path));
+                                   path);
                        ret = WIMLIB_ERR_READ;
                }
        } else if (export_ctx.bytes_remaining != 0) {
                ERROR("Only could read %"PRIu64" of %"PRIu64" bytes from "
                      "encrypted file \"%ls\"",
                      size - export_ctx.bytes_remaining, size,
-                     printable_path(path));
+                     path);
                ret = WIMLIB_ERR_READ;
        } else {
                ret = 0;
@@ -532,7 +532,6 @@ winnt_get_short_name(HANDLE h, struct wim_dentry *dentry)
  */
 static noinline_for_stack int
 winnt_load_security_descriptor(HANDLE h, struct wim_inode *inode,
-                              const wchar_t *full_path,
                               struct winnt_scan_ctx *ctx)
 {
        SECURITY_INFORMATION requestedInformation;
@@ -650,7 +649,7 @@ out:
                FREE(buf);
        if (!NT_SUCCESS(status)) {
                winnt_error(status, L"\"%ls\": Can't read security descriptor",
-                           printable_path(full_path));
+                           printable_path(ctx));
                return WIMLIB_ERR_STAT;
        }
        return 0;
@@ -659,7 +658,7 @@ out:
 /* Load a file's object ID into the corresponding WIM inode.  */
 static noinline_for_stack int
 winnt_load_object_id(HANDLE h, struct wim_inode *inode,
-                    const wchar_t *full_path, struct winnt_scan_ctx *ctx)
+                    struct winnt_scan_ctx *ctx)
 {
        FILE_OBJECTID_BUFFER buffer;
        NTSTATUS status;
@@ -683,7 +682,7 @@ winnt_load_object_id(HANDLE h, struct wim_inode *inode,
 
        if (!NT_SUCCESS(status)) {
                winnt_error(status, L"\"%ls\": Can't read object ID",
-                           printable_path(full_path));
+                           printable_path(ctx));
                return WIMLIB_ERR_STAT;
        }
 
@@ -699,17 +698,13 @@ winnt_load_object_id(HANDLE h, struct wim_inode *inode,
 static int
 winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                                  HANDLE cur_dir,
-                                 wchar_t *full_path,
-                                 size_t full_path_nchars,
-                                 wchar_t *relative_path,
+                                 const wchar_t *relative_path,
                                  size_t relative_path_nchars,
                                  const wchar_t *filename,
                                  struct winnt_scan_ctx *ctx);
 
 static int
 winnt_recurse_directory(HANDLE h,
-                       wchar_t *full_path,
-                       size_t full_path_nchars,
                        struct wim_dentry *parent,
                        struct winnt_scan_ctx *ctx)
 {
@@ -736,33 +731,27 @@ winnt_recurse_directory(HANDLE h,
                        if (!should_ignore_filename(info->FileName,
                                                    info->FileNameLength / 2))
                        {
-                               wchar_t *p;
-                               wchar_t *filename;
                                struct wim_dentry *child;
-
-                               p = full_path + full_path_nchars;
-                               /* Only add a backslash if we don't already have
-                                * one.  This prevents a duplicate backslash
-                                * from being added when the path to the capture
-                                * dir had a trailing backslash.  */
-                               if (*(p - 1) != L'\\')
-                                       *p++ = L'\\';
-                               filename = p;
-                               p = wmempcpy(filename, info->FileName,
-                                            info->FileNameLength / 2);
-                               *p = '\0';
+                               size_t orig_path_nchars;
+                               const wchar_t *filename;
+
+                               ret = WIMLIB_ERR_NOMEM;
+                               filename = pathbuf_append_name(ctx->params,
+                                                              info->FileName,
+                                                              info->FileNameLength / 2,
+                                                              &orig_path_nchars);
+                               if (!filename)
+                                       goto out_free_buf;
 
                                ret = winnt_build_dentry_tree_recursive(
                                                        &child,
                                                        h,
-                                                       full_path,
-                                                       p - full_path,
                                                        filename,
                                                        info->FileNameLength / 2,
                                                        filename,
                                                        ctx);
 
-                               full_path[full_path_nchars] = L'\0';
+                               pathbuf_truncate(ctx->params, orig_path_nchars);
 
                                if (ret)
                                        goto out_free_buf;
@@ -778,7 +767,7 @@ winnt_recurse_directory(HANDLE h,
 
        if (unlikely(status != STATUS_NO_MORE_FILES)) {
                winnt_error(status, L"\"%ls\": Can't read directory",
-                           printable_path(full_path));
+                           printable_path(ctx));
                ret = WIMLIB_ERR_READ;
        }
 out_free_buf:
@@ -910,7 +899,7 @@ out_close_root_dir:
 }
 
 static int
-winnt_rpfix_progress(struct scan_params *params, const wchar_t *path,
+winnt_rpfix_progress(struct scan_params *params,
                     const struct link_reparse_point *link, int scan_status)
 {
        size_t print_name_nchars = link->print_name_nbytes / sizeof(wchar_t);
@@ -919,14 +908,13 @@ winnt_rpfix_progress(struct scan_params *params, const wchar_t *path,
        wmemcpy(print_name0, link->print_name, print_name_nchars);
        print_name0[print_name_nchars] = L'\0';
 
-       params->progress.scan.cur_path = path;
        params->progress.scan.symlink_target = print_name0;
        return do_scan_progress(params, scan_status, NULL);
 }
 
 static int
 winnt_try_rpfix(struct reparse_buffer_disk *rpbuf, u16 *rpbuflen_p,
-               const wchar_t *path, struct scan_params *params)
+               struct scan_params *params)
 {
        struct link_reparse_point link;
        const wchar_t *rel_target;
@@ -970,7 +958,7 @@ winnt_try_rpfix(struct reparse_buffer_disk *rpbuf, u16 *rpbuflen_p,
        if (rel_target == link.substitute_name) {
                /* Target points outside of the tree being captured or had an
                 * unrecognized path format.  Don't adjust it.  */
-               return winnt_rpfix_progress(params, path, &link,
+               return winnt_rpfix_progress(params, &link,
                                            WIMLIB_SCAN_DENTRY_NOT_FIXED_SYMLINK);
        }
 
@@ -1006,7 +994,7 @@ winnt_try_rpfix(struct reparse_buffer_disk *rpbuf, u16 *rpbuflen_p,
        if (make_link_reparse_point(&link, rpbuf, rpbuflen_p))
                return 0;
 
-       ret = winnt_rpfix_progress(params, path, &link,
+       ret = winnt_rpfix_progress(params, &link,
                                   WIMLIB_SCAN_DENTRY_FIXED_SYMLINK);
        if (ret)
                return ret;
@@ -1019,7 +1007,7 @@ winnt_try_rpfix(struct reparse_buffer_disk *rpbuf, u16 *rpbuflen_p,
  * capture root.  */
 static noinline_for_stack int
 winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
-                       const wchar_t *full_path, struct scan_params *params)
+                       struct winnt_scan_ctx *ctx)
 {
        struct reparse_buffer_disk rpbuf;
        NTSTATUS status;
@@ -1030,7 +1018,7 @@ winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
        if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) {
                /* See comment above assign_stream_types_encrypted()  */
                WARNING("Ignoring reparse data of encrypted file \"%ls\"",
-                       printable_path(full_path));
+                       printable_path(ctx));
                return 0;
        }
 
@@ -1038,7 +1026,7 @@ winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
                             NULL, 0, &rpbuf, sizeof(rpbuf), &len);
        if (!NT_SUCCESS(status)) {
                winnt_error(status, L"\"%ls\": Can't get reparse point",
-                           printable_path(full_path));
+                           printable_path(ctx));
                return WIMLIB_ERR_READLINK;
        }
 
@@ -1046,7 +1034,7 @@ winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
 
        if (unlikely(rpbuflen < REPARSE_DATA_OFFSET)) {
                ERROR("\"%ls\": reparse point buffer is too short",
-                     printable_path(full_path));
+                     printable_path(ctx));
                return WIMLIB_ERR_INVALID_REPARSE_DATA;
        }
 
@@ -1065,8 +1053,8 @@ winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
                return 0;
        }
 
-       if (params->add_flags & WIMLIB_ADD_FLAG_RPFIX) {
-               ret = winnt_try_rpfix(&rpbuf, &rpbuflen, full_path, params);
+       if (ctx->params->add_flags & WIMLIB_ADD_FLAG_RPFIX) {
+               ret = winnt_try_rpfix(&rpbuf, &rpbuflen, ctx->params);
                if (ret == RP_FIXED)
                        inode->i_rp_flags &= ~WIM_RP_FLAG_NOT_FIXED;
                else if (ret)
@@ -1081,7 +1069,7 @@ winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
                                        NO_STREAM_NAME,
                                        rpbuf.rpdata,
                                        rpbuflen - REPARSE_DATA_OFFSET,
-                                       params->blob_table))
+                                       ctx->params->blob_table))
                return WIMLIB_ERR_NOMEM;
 
        return 0;
@@ -1110,7 +1098,7 @@ win32_get_encrypted_file_size(const wchar_t *path, bool is_dir, u64 *size_ret)
        if (err != ERROR_SUCCESS) {
                win32_error(err,
                            L"Failed to open encrypted file \"%ls\" for raw read",
-                           printable_path(path));
+                           path);
                return WIMLIB_ERR_OPEN;
        }
        *size_ret = 0;
@@ -1119,7 +1107,7 @@ win32_get_encrypted_file_size(const wchar_t *path, bool is_dir, u64 *size_ret)
        if (err != ERROR_SUCCESS) {
                win32_error(err,
                            L"Failed to read raw encrypted data from \"%ls\"",
-                           printable_path(path));
+                           path);
                ret = WIMLIB_ERR_READ;
        } else {
                ret = 0;
@@ -1130,9 +1118,10 @@ win32_get_encrypted_file_size(const wchar_t *path, bool is_dir, u64 *size_ret)
 
 static int
 winnt_scan_efsrpc_raw_data(struct wim_inode *inode,
-                          wchar_t *path, size_t path_nchars,
                           struct winnt_scan_ctx *ctx)
 {
+       wchar_t *path = ctx->params->cur_path;
+       size_t path_nchars = ctx->params->cur_path_nchars;
        const bool is_dir = (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY);
        struct windows_file *windows_file;
        u64 size;
@@ -1192,8 +1181,7 @@ get_data_stream_name(const wchar_t *raw_stream_name, size_t raw_stream_name_ncha
 }
 
 static int
-winnt_scan_data_stream(const wchar_t *path, size_t path_nchars,
-                      wchar_t *raw_stream_name, size_t raw_stream_name_nchars,
+winnt_scan_data_stream(wchar_t *raw_stream_name, size_t raw_stream_name_nchars,
                       u64 stream_size, struct wim_inode *inode,
                       struct winnt_scan_ctx *ctx)
 {
@@ -1211,7 +1199,8 @@ winnt_scan_data_stream(const wchar_t *path, size_t path_nchars,
 
        stream_name[stream_name_nchars] = L'\0';
 
-       windows_file = alloc_windows_file(path, path_nchars,
+       windows_file = alloc_windows_file(ctx->params->cur_path,
+                                         ctx->params->cur_path_nchars,
                                          stream_name, stream_name_nchars,
                                          ctx->snapshot, false);
        return add_stream(inode, windows_file, stream_size, STREAM_TYPE_DATA,
@@ -1233,8 +1222,7 @@ winnt_scan_data_stream(const wchar_t *path, size_t path_nchars,
  *   already present in Windows XP.
  */
 static noinline_for_stack int
-winnt_scan_data_streams(HANDLE h, const wchar_t *path, size_t path_nchars,
-                       struct wim_inode *inode, u64 file_size,
+winnt_scan_data_streams(HANDLE h, struct wim_inode *inode, u64 file_size,
                        struct winnt_scan_ctx *ctx)
 {
        int ret;
@@ -1283,7 +1271,7 @@ winnt_scan_data_streams(HANDLE h, const wchar_t *path, size_t path_nchars,
                default:
                        winnt_error(status,
                                    L"\"%ls\": Failed to query stream information",
-                                   printable_path(path));
+                                   printable_path(ctx));
                        ret = WIMLIB_ERR_READ;
                        goto out_free_buf;
                }
@@ -1299,8 +1287,7 @@ winnt_scan_data_streams(HANDLE h, const wchar_t *path, size_t path_nchars,
        info = (FILE_STREAM_INFORMATION *)buf;
        for (;;) {
                /* Load the stream information.  */
-               ret = winnt_scan_data_stream(path, path_nchars,
-                                            info->StreamName,
+               ret = winnt_scan_data_stream(info->StreamName,
                                             info->StreamNameLength / 2,
                                             info->StreamSize.QuadPart,
                                             inode, ctx);
@@ -1330,8 +1317,8 @@ unnamed_only:
 
        {
                wchar_t stream_name[] = L"::$DATA";
-               ret = winnt_scan_data_stream(path, path_nchars, stream_name, 7,
-                                            file_size, inode, ctx);
+               ret = winnt_scan_data_stream(stream_name, 7, file_size,
+                                            inode, ctx);
        }
 out_free_buf:
        /* Free buffer if allocated on heap.  */
@@ -1375,8 +1362,7 @@ set_sort_key(struct wim_inode *inode, u64 sort_key)
 
 static inline bool
 should_try_to_use_wimboot_hash(const struct wim_inode *inode,
-                              const struct winnt_scan_ctx *ctx,
-                              const struct scan_params *params)
+                              const struct winnt_scan_ctx *ctx)
 {
        /* Directories and encrypted files aren't valid for external backing. */
        if (inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
@@ -1388,7 +1374,7 @@ should_try_to_use_wimboot_hash(const struct wim_inode *inode,
         * fixup if WOF may be attached. */
        if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
                return (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_WOF) &&
-                       (params->add_flags & WIMLIB_ADD_FLAG_WIMBOOT);
+                       (ctx->params->add_flags & WIMLIB_ADD_FLAG_WIMBOOT);
        return !ctx->wof_not_attached;
 }
 
@@ -1410,7 +1396,7 @@ should_try_to_use_wimboot_hash(const struct wim_inode *inode,
  */
 static noinline_for_stack int
 try_to_use_wimboot_hash(HANDLE h, struct wim_inode *inode,
-                       struct winnt_scan_ctx *ctx, const wchar_t *full_path)
+                       struct winnt_scan_ctx *ctx)
 {
        struct blob_table *blob_table = ctx->params->blob_table;
        struct wim_inode_stream *reparse_strm = NULL;
@@ -1479,7 +1465,7 @@ try_to_use_wimboot_hash(HANDLE h, struct wim_inode *inode,
                if (status != STATUS_SUCCESS) {
                        winnt_error(status,
                                    L"\"%ls\": FSCTL_GET_EXTERNAL_BACKING failed",
-                                   full_path);
+                                   printable_path(ctx));
                        return WIMLIB_ERR_STAT;
                }
 
@@ -1558,8 +1544,7 @@ get_file_info(HANDLE h, struct file_info *info)
 }
 
 static void
-get_volume_information(HANDLE h, const wchar_t *full_path,
-                      struct winnt_scan_ctx *ctx)
+get_volume_information(HANDLE h, struct winnt_scan_ctx *ctx)
 {
        u8 _attr_info[sizeof(FILE_FS_ATTRIBUTE_INFORMATION) + 128] _aligned_attribute(8);
        FILE_FS_ATTRIBUTE_INFORMATION *attr_info = (void *)_attr_info;
@@ -1578,7 +1563,7 @@ get_volume_information(HANDLE h, const wchar_t *full_path,
                                !wmemcmp(attr_info->FileSystemName, L"NTFS", 4);
        } else {
                winnt_warning(status, L"\"%ls\": Can't get volume attributes",
-                             printable_path(full_path));
+                             printable_path(ctx));
        }
 
        /* Get volume ID.  */
@@ -1593,7 +1578,7 @@ get_volume_information(HANDLE h, const wchar_t *full_path,
                ctx->params->capture_root_dev = vol_info.VolumeSerialNumber;
        } else {
                winnt_warning(status, L"\"%ls\": Can't get volume ID",
-                             printable_path(full_path));
+                             printable_path(ctx));
        }
 
        /* Get inode number.  */
@@ -1602,16 +1587,14 @@ get_volume_information(HANDLE h, const wchar_t *full_path,
                ctx->params->capture_root_ino = file_info.ino;
        } else {
                winnt_warning(status, L"\"%ls\": Can't get file information",
-                             printable_path(full_path));
+                             printable_path(ctx));
        }
 }
 
 static int
 winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                                  HANDLE cur_dir,
-                                 wchar_t *full_path,
-                                 size_t full_path_nchars,
-                                 wchar_t *relative_path,
+                                 const wchar_t *relative_path,
                                  size_t relative_path_nchars,
                                  const wchar_t *filename,
                                  struct winnt_scan_ctx *ctx)
@@ -1624,7 +1607,7 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
        struct file_info file_info;
        u64 sort_key;
 
-       ret = try_exclude(full_path, ctx->params);
+       ret = try_exclude(ctx->params);
        if (unlikely(ret < 0)) /* Excluded? */
                goto out_progress;
        if (unlikely(ret > 0)) /* Error? */
@@ -1643,7 +1626,7 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
        if (unlikely(!NT_SUCCESS(status))) {
                if (status == STATUS_DELETE_PENDING) {
                        WARNING("\"%ls\": Deletion pending; skipping file",
-                               printable_path(full_path));
+                               printable_path(ctx));
                        ret = 0;
                        goto out;
                }
@@ -1651,12 +1634,12 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                        ERROR("Can't open \"%ls\":\n"
                              "        File is in use by another process! "
                              "Consider using snapshot (VSS) mode.",
-                             printable_path(full_path));
+                             printable_path(ctx));
                        ret = WIMLIB_ERR_OPEN;
                        goto out;
                }
                winnt_error(status, L"\"%ls\": Can't open file",
-                           printable_path(full_path));
+                           printable_path(ctx));
                if (status == STATUS_FVE_LOCKED_VOLUME)
                        ret = WIMLIB_ERR_FVE_LOCKED_VOLUME;
                else
@@ -1668,7 +1651,7 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
        status = get_file_info(h, &file_info);
        if (!NT_SUCCESS(status)) {
                winnt_error(status, L"\"%ls\": Can't get file information",
-                           printable_path(full_path));
+                           printable_path(ctx));
                ret = WIMLIB_ERR_STAT;
                goto out;
        }
@@ -1724,19 +1707,19 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
        if (!(ctx->params->add_flags & WIMLIB_ADD_FLAG_NO_ACLS)
            && (ctx->vol_flags & FILE_PERSISTENT_ACLS))
        {
-               ret = winnt_load_security_descriptor(h, inode, full_path, ctx);
+               ret = winnt_load_security_descriptor(h, inode, ctx);
                if (ret)
                        goto out;
        }
 
        /* Get the file's object ID.  */
-       ret = winnt_load_object_id(h, inode, full_path, ctx);
+       ret = winnt_load_object_id(h, inode, ctx);
        if (ret)
                goto out;
 
        /* If this is a reparse point, load the reparse data.  */
        if (unlikely(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
-               ret = winnt_load_reparse_data(h, inode, full_path, ctx->params);
+               ret = winnt_load_reparse_data(h, inode, ctx);
                if (ret)
                        goto out;
        }
@@ -1754,8 +1737,7 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                 * needed.  */
                NtClose(h);
                h = NULL;
-               ret = winnt_scan_efsrpc_raw_data(inode, full_path,
-                                                full_path_nchars, ctx);
+               ret = winnt_scan_efsrpc_raw_data(inode, ctx);
                if (ret)
                        goto out;
        } else {
@@ -1770,8 +1752,6 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                 * the EFSRPC data and the named data stream(s)...!
                 */
                ret = winnt_scan_data_streams(h,
-                                             full_path,
-                                             full_path_nchars,
                                              inode,
                                              file_info.end_of_file,
                                              ctx);
@@ -1779,8 +1759,8 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                        goto out;
        }
 
-       if (unlikely(should_try_to_use_wimboot_hash(inode, ctx, ctx->params))) {
-               ret = try_to_use_wimboot_hash(h, inode, ctx, full_path);
+       if (unlikely(should_try_to_use_wimboot_hash(inode, ctx))) {
+               ret = try_to_use_wimboot_hash(h, inode, ctx);
                if (ret)
                        goto out;
        }
@@ -1801,21 +1781,16 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                                      &h);
                if (!NT_SUCCESS(status)) {
                        winnt_error(status, L"\"%ls\": Can't open directory",
-                                   printable_path(full_path));
+                                   printable_path(ctx));
                        ret = WIMLIB_ERR_OPEN;
                        goto out;
                }
-               ret = winnt_recurse_directory(h,
-                                             full_path,
-                                             full_path_nchars,
-                                             root,
-                                             ctx);
+               ret = winnt_recurse_directory(h, root, ctx);
                if (ret)
                        goto out;
        }
 
 out_progress:
-       ctx->params->progress.scan.cur_path = full_path;
        if (likely(root))
                ret = do_scan_progress(ctx->params, WIMLIB_SCAN_DENTRY_OK, inode);
        else
@@ -1826,7 +1801,7 @@ out:
        if (unlikely(ret)) {
                free_dentry_tree(root, ctx->params->blob_table);
                root = NULL;
-               ret = report_scan_error(ctx->params, ret, full_path);
+               ret = report_scan_error(ctx->params, ret);
        }
        *root_ret = root;
        return ret;
@@ -2616,7 +2591,6 @@ security_map_destroy(struct security_map *map)
  */
 static int
 generate_wim_structures_recursive(struct wim_dentry **root_ret,
-                                 wchar_t *path, size_t path_nchars,
                                  const wchar_t *filename, bool is_primary_name,
                                  struct ntfs_inode *ni,
                                  struct winnt_scan_ctx *ctx,
@@ -2642,17 +2616,15 @@ generate_wim_structures_recursive(struct wim_dentry **root_ret,
        {
                ret = winnt_build_dentry_tree_recursive(&root,
                                                        NULL,
-                                                       path,
-                                                       path_nchars,
-                                                       path,
-                                                       path_nchars,
+                                                       ctx->params->cur_path,
+                                                       ctx->params->cur_path_nchars,
                                                        filename,
                                                        ctx);
                goto out;
        }
 
        /* Test for exclusion based on path.  */
-       ret = try_exclude(path, ctx->params);
+       ret = try_exclude(ctx->params);
        if (unlikely(ret < 0)) /* Excluded? */
                goto out_progress;
        if (unlikely(ret > 0)) /* Error? */
@@ -2706,17 +2678,18 @@ generate_wim_structures_recursive(struct wim_dentry **root_ret,
                        /* Create a mapping for this security ID and insert it
                         * into the security map.  */
 
-                       status = winnt_open(path, path_nchars,
+                       status = winnt_open(ctx->params->cur_path,
+                                           ctx->params->cur_path_nchars,
                                            READ_CONTROL |
                                                ACCESS_SYSTEM_SECURITY, &h);
                        if (!NT_SUCCESS(status)) {
                                winnt_error(status, L"Can't open \"%ls\" to "
                                            "read security descriptor",
-                                           printable_path(path));
+                                           printable_path(ctx));
                                ret = WIMLIB_ERR_OPEN;
                                goto out;
                        }
-                       ret = winnt_load_security_descriptor(h, inode, path, ctx);
+                       ret = winnt_load_security_descriptor(h, inode, ctx);
                        NtClose(h);
                        if (ret)
                                goto out;
@@ -2741,16 +2714,16 @@ generate_wim_structures_recursive(struct wim_dentry **root_ret,
                    !(ctx->vol_flags & FILE_SUPPORTS_OPEN_BY_FILE_ID) ||
                    !(ctx->params->add_flags & WIMLIB_ADD_FLAG_FILE_PATHS_UNNEEDED))
                {
-                       windows_file = alloc_windows_file(path,
-                                                         path_nchars,
+                       windows_file = alloc_windows_file(ctx->params->cur_path,
+                                                         ctx->params->cur_path_nchars,
                                                          ns->name,
                                                          wcslen(ns->name),
                                                          ctx->snapshot,
                                                          false);
                } else {
                        windows_file = alloc_windows_file_for_file_id(ni->ino,
-                                                                     path,
-                                                                     ctx->params->capture_root_nchars + 1,
+                                                                     ctx->params->cur_path,
+                                                                     ctx->params->root_path_nchars,
                                                                      ctx->snapshot);
                }
 
@@ -2771,20 +2744,18 @@ generate_wim_structures_recursive(struct wim_dentry **root_ret,
                const struct ntfs_dentry *nd = ni->first_child;
 
                while (nd != NULL) {
-                       const size_t name_len = wcslen(nd->name);
-                       wchar_t *p = path + path_nchars;
+                       size_t orig_path_nchars;
                        struct wim_dentry *child;
                        const struct ntfs_dentry *next = nd->next_child;
 
-                       if (*(p - 1) != L'\\')
-                               *p++ = L'\\';
-                       p = wmempcpy(p, nd->name, name_len);
-                       *p = '\0';
+                       ret = WIMLIB_ERR_NOMEM;
+                       if (!pathbuf_append_name(ctx->params, nd->name,
+                                                wcslen(nd->name),
+                                                &orig_path_nchars))
+                               goto out;
 
                        ret = generate_wim_structures_recursive(
                                        &child,
-                                       path,
-                                       p - path,
                                        nd->name,
                                        nd->is_primary,
                                        (void *)nd - nd->offset_from_inode,
@@ -2792,7 +2763,7 @@ generate_wim_structures_recursive(struct wim_dentry **root_ret,
                                        inode_map,
                                        security_map);
 
-                       path[path_nchars] = L'\0';
+                       pathbuf_truncate(ctx->params, orig_path_nchars);
 
                        if (ret)
                                goto out;
@@ -2803,7 +2774,6 @@ generate_wim_structures_recursive(struct wim_dentry **root_ret,
        }
 
 out_progress:
-       ctx->params->progress.scan.cur_path = path;
        if (likely(root))
                ret = do_scan_progress(ctx->params, WIMLIB_SCAN_DENTRY_OK, inode);
        else
@@ -2823,12 +2793,14 @@ out:
 }
 
 static int
-winnt_build_dentry_tree_fast(struct wim_dentry **root_ret, wchar_t *path,
-                            size_t path_nchars, struct winnt_scan_ctx *ctx)
+winnt_build_dentry_tree_fast(struct wim_dentry **root_ret,
+                            struct winnt_scan_ctx *ctx)
 {
        struct ntfs_inode_map inode_map = { .root = NULL };
        struct security_map security_map = { .root = NULL };
        struct ntfs_inode *root = NULL;
+       wchar_t *path = ctx->params->cur_path;
+       size_t path_nchars = ctx->params->cur_path_nchars;
        bool adjust_path;
        int ret;
 
@@ -2857,8 +2829,7 @@ winnt_build_dentry_tree_fast(struct wim_dentry **root_ret, wchar_t *path,
 
        root->num_aliases = 1;
 
-       ret = generate_wim_structures_recursive(root_ret, path, path_nchars,
-                                               L"", false, root, ctx,
+       ret = generate_wim_structures_recursive(root_ret, L"", false, root, ctx,
                                                &inode_map, &security_map);
 out:
        ntfs_inode_map_destroy(&inode_map);
@@ -2872,28 +2843,17 @@ out:
  *                 Entry point for directory tree scans on Windows            *
  *----------------------------------------------------------------------------*/
 
-#define WINDOWS_NT_MAX_PATH 32768
-
 int
 win32_build_dentry_tree(struct wim_dentry **root_ret,
                        const wchar_t *root_disk_path,
                        struct scan_params *params)
 {
-       wchar_t *path = NULL;
        struct winnt_scan_ctx ctx = { .params = params };
        UNICODE_STRING ntpath;
-       size_t ntpath_nchars;
        HANDLE h = NULL;
        NTSTATUS status;
        int ret;
 
-       /* WARNING: There is no check for overflow later when this buffer is
-        * being used!  But it's as long as the maximum path length understood
-        * by Windows NT (which is NOT the same as MAX_PATH).  */
-       path = MALLOC((WINDOWS_NT_MAX_PATH + 1) * sizeof(wchar_t));
-       if (!path)
-               return WIMLIB_ERR_NOMEM;
-
        if (params->add_flags & WIMLIB_ADD_FLAG_SNAPSHOT)
                ret = vss_create_snapshot(root_disk_path, &ntpath, &ctx.snapshot);
        else
@@ -2903,28 +2863,21 @@ win32_build_dentry_tree(struct wim_dentry **root_ret,
                goto out;
 
        if (ntpath.Length < 4 * sizeof(wchar_t) ||
-           ntpath.Length > WINDOWS_NT_MAX_PATH * sizeof(wchar_t) ||
            wmemcmp(ntpath.Buffer, L"\\??\\", 4))
        {
                ERROR("\"%ls\": unrecognized path format", root_disk_path);
                ret = WIMLIB_ERR_INVALID_PARAM;
        } else {
-               ntpath_nchars = ntpath.Length / sizeof(wchar_t);
-               wmemcpy(path, ntpath.Buffer, ntpath_nchars);
-               path[ntpath_nchars] = L'\0';
-
-               params->capture_root_nchars = ntpath_nchars;
-               if (path[ntpath_nchars - 1] == L'\\')
-                       params->capture_root_nchars--;
-               ret = 0;
+               ret = pathbuf_init(params, ntpath.Buffer);
        }
        HeapFree(GetProcessHeap(), 0, ntpath.Buffer);
        if (ret)
                goto out;
 
-       status = winnt_open(path, ntpath_nchars, FILE_READ_ATTRIBUTES, &h);
+       status = winnt_open(params->cur_path, params->cur_path_nchars,
+                           FILE_READ_ATTRIBUTES, &h);
        if (!NT_SUCCESS(status)) {
-               winnt_error(status, L"Can't open \"%ls\"", printable_path(path));
+               winnt_error(status, L"Can't open \"%ls\"", root_disk_path);
                if (status == STATUS_FVE_LOCKED_VOLUME)
                        ret = WIMLIB_ERR_FVE_LOCKED_VOLUME;
                else
@@ -2932,14 +2885,13 @@ win32_build_dentry_tree(struct wim_dentry **root_ret,
                goto out;
        }
 
-       get_volume_information(h, path, &ctx);
+       get_volume_information(h, &ctx);
 
        NtClose(h);
 
 #ifdef ENABLE_FAST_MFT_SCAN
        if (ctx.is_ntfs && !_wgetenv(L"WIMLIB_DISABLE_QUERY_FILE_LAYOUT")) {
-               ret = winnt_build_dentry_tree_fast(root_ret, path,
-                                                  ntpath_nchars, &ctx);
+               ret = winnt_build_dentry_tree_fast(root_ret, &ctx);
                if (ret >= 0 && ret != WIMLIB_ERR_UNSUPPORTED)
                        goto out;
                if (ret >= 0) {
@@ -2950,12 +2902,11 @@ win32_build_dentry_tree(struct wim_dentry **root_ret,
        }
 #endif
        ret = winnt_build_dentry_tree_recursive(root_ret, NULL,
-                                               path, ntpath_nchars,
-                                               path, ntpath_nchars,
+                                               params->cur_path,
+                                               params->cur_path_nchars,
                                                L"", &ctx);
 out:
        vss_put_snapshot(ctx.snapshot);
-       FREE(path);
        if (ret == 0)
                winnt_do_scan_warnings(root_disk_path, &ctx);
        return ret;